American sibling song-and-dance team Tom (Fred Astaire) and Ellen Bowen (Jane Powell) are in London in 1947, when all of England is in a tizzy over the impending nuptials of Princess Elizabeth and Prince Philip. Ellen falls head over heels for the dashing Lord John Brindale (Peter Lawford), and Tom becomes equally smitten with the elegant Anne Ashmond (Sarah Churchill). The film features one of Astaire's most legendary dance performances, dancing across the ceiling of a hotel room.